A strategic approach to the synthesis of novel class of dispiroheterocyclic derivatives through 1,3 dipolar cycloaddition of azomethine ylide with (E)-3-arylidene-2,3-dihydro-8-nitro-4-quinolone

Synthesis and X-ray study of dispiro 8-nitroquinolone analogues and their cytotoxic properties against human cervical cancer HeLa cells

“…Initially, the dipolarophiles 3a-d were synthesized by a Knoevenagel condensation of 8-nitro-2,3-dihydro-1Hquinolin-4-one 1 with aromatic aldehydes 2a-d in the presence of a pyrrolidine base in ethanol affording (E)-3arylidene-2,3-dihydro-8-nitro-4-quinolones 3a-d in quantitative yields. 31 In the next step, a one pot three-component 1,3-dipolar cycloaddition reaction was carried out between (E)-3arylidene-2,3-dihydro-8-nitro-4-quinolones 3a-d, and the dipole generated from isatin derivatives 5a-c and benzylamine 4 (Scheme 1).…”

Synthesis of 3‐Methylidene‐1‐tosyl‐2,3‐dihydroquinolin‐4(1H)‐ones as Potent Cytotoxic Agents

“…Consequently, several approaches to 3‐alkylidene(arylidene)‐2,3‐dihydroquinolin‐4‐ones 1 have been reported so far. The most common approach is condensation of the appropriate 3,4‐dihydroquinolin‐4‐ones with aromatic aldehydes . Another general method leading to 3‐methylidene‐3,4‐dihydroquinolin‐4‐ones involves palladium(0)‐catalyzed oxidative addition of N‐functionalized aryl iodides followed by low‐pressure carbonylation, allene insertion and capture of the resulting P‐allyl palladium(II) species by internal N‐nucleophile .…”

“…Synthetic utility of 3‐alkylidene(arylidene)‐2,3‐dihydroquinolin‐4‐ones 1 was also investigated. These compounds proved to be versatile intermediates in the synthesis of martinelline chiral core, dispiroheterocyclic derivatives, heteroannulated 8‐nitroquinolines or 2‐aryl‐3‐benzylquinolin‐4‐ones. [ ][ ] Surprisingly, only few of the synthesized 3‐alkylidene(arylidene)‐2,3‐dihydroquinolin‐4‐ones 1 were tested for their biological activity so far.…”

Synthesis of novel dispiropyrrolothiazoles by three-component 1,3-dipolar cycloaddition and evaluation of their antimycobacterial activity

“…Moreover, an additional hydrogen bond takes place through in exo-TS1, between one of the methylene hydrogen atoms of dipolarophile 10a with the carbonyl of the azomethine ylide 12a (2.406 Å). 20 The analysis of the thermodynamic parameters (Gibbs free energy (DG), enthalpy (DH) and entropy (DS), between reactants and products) of the studied reactions. It is observed that the lowest DG values stem from the endo approach on 14 0 a.…”